Re: [PATCH] counter: ti-eqep: Fix runtime PM imbalance in ti_eqep_probe()

[Jonathan Cameron]

On Wed, 16 Sep 2026 07:22:47 +0000
Wentao Liang <vulab@xxxxxxxxxxx> wrote:

> In ti_eqep_probe(), runtime PM is enabled and acquired via
> pm_runtime_get_sync(dev). However, if devm_clk_get_enabled() fails,
> the function returns directly without calling pm_runtime_put_sync()
> and pm_runtime_disable(), leaving the runtime PM usage count and
> enable state unbalanced.
> 
> Add the missing pm_runtime_put_sync() and pm_runtime_disable() calls
> on the clock error path.
> 
> Fixes: 0cf81c73e4c6 ("counter: ti-eqep: enable clock at probe")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
> ---
>  drivers/counter/ti-eqep.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c
> index d21c157e531a..84fbf500b0f8 100644
> --- a/drivers/counter/ti-eqep.c
> +++ b/drivers/counter/ti-eqep.c
> @@ -548,8 +548,11 @@ static int ti_eqep_probe(struct platform_device *pdev)
>  	pm_runtime_get_sync(dev);
>  
>  	clk = devm_clk_get_enabled(dev, NULL);
> -	if (IS_ERR(clk))
> +	if (IS_ERR(clk)) {
> +		pm_runtime_put_sync(dev);
> +		pm_runtime_disable(dev);

Having manual cleanup immediately after a devm call is not a good sign as
it will be out of order.  Use devm_pm_runtime_enable() and consider if the
pm_runtime_get_sync() that the put is reversing is actually needed.
I suspect not.

>  		return dev_err_probe(dev, PTR_ERR(clk), "failed to enable clock\n");
> +	}
>  
>  	err = counter_add(counter);
>  	if (err < 0) {